At what compression ratio do you need premium fuel?
To release all the potential power of 91 octane gasoline, it is necessary for an engine to have a compression ratio higher than 9.3 : 1.
What octane do you use for 10 1 compression?
Most stock gas engines have a compression ratio around 10:1 and run just fine on regular 87-octane gas.
What octane is needed for 9.5 to 1 compression?
The standard recommendation for street engines running on pump gas has always been to shoot for a 9.0:1 to perhaps 9.5:1 compression ratio. This is in order for the engine to safely work with pump gas, which for much of the country, is limited to 91-octane.
What is the compression ratio for 95 octane?
95 Octane. Gasoline with this octane number is known in Indonesia under the brands Pertamax Plus (produced by Pertamina), Super Extra (produced by Shell), and Primax (produced by Petronas). This type of gasoline is advisable for car engines with compression ratios of 11:1 to 12:1.
What compression is best for 93 octane?
If the cylinders are sealing up well, I look for 190 psi as a lower limit with preferably 200 psi as a target when using 93-octane fuel. For every octane number less than 93, the compression pressure needs to be about 5 psi less to avoid detonation under normal circumstances.
What is the highest compression ratio for 93 octane?
We are being told by most piston manufacturers that 9.5:1 is the most you should run in an engine with cast iron heads on 93 octane pump gas. Because aluminum conducts (dissipates to the cooling system) heat much faster than cast iron does, you can run 10.5:1 with aluminum heads on 93 octane.
What octane is needed for 10.5 compression?
Before computer controlled ignition systems anything greater than 10:1 would quite likely require premium, but today an engine with a compression ratio of 10.5:1 can run on 87 octane (or at least my ’14 Honda Accord can).
What is the lowest compression ratio for 93 octane?
However, general guidelines would be that if you car has a high compression ratio, above 8.5:1 you should use 95, and if your car has a compression ratio below 8.5:1 you should use 93.
What octane Do I needed for 12.5 to 1 compression?
At 12:1 compression, # 93 octane may be adequate for a normally aspirated engine with electronic controls, variable valve timing and a ‘knock’ sensor. It will probably not be sufficient for a supercharged or turbocharged engine with this compression ratio.
What is the compression ratio for 98 octane gas?
93 is therefore ideal for lower compression ratio engines (generally low performance engines with a *ratio below 8.5:1), whereas 95 and 98 (*Ratios between 8.5:1 and 10:1) are more stable and suitable for high compression engines (often higher performance engines).
What is the compression ratio for 93 octane?
What is the compression ratio for 100 octane?
It has an octane rating (AKI) of 100 and can be used in engines with compression ratios up to 12 to 1 (with hardened valve seats).